NOTCH3 and cerebral arteriopathy with subcortical infarcts and leukoencephalopathy: cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary brain small vessel disease caused by pathogenic variants in the NOTCH3 gene, leading to NOTCH3 protein accumulation and degeneration of vascular smooth muscle cells (VSMCs).